When the indie film musical Once was released five years ago, it became a critical and box-office sensation. This touching tale of the relationship between a Dublin Irish street musician and the Czech émigré who helps him find his musical voice had a refreshingly modest charm. So it was heartening to hear that its theatrical adaptation would be receiving its world premiere at the New York Theatre Workshop, clearly not a venue for glitzy, overblown musicals.

And yet, for all the modesty of its approach, this version still seems somewhat glossy and bloated. For one thing, the simple tale, told in just 90 minutes on film, now runs nearly two-and-a-half hours. And the lead characters, dubbed just “Guy” and “Girl,” are no longer the scruffy, realistic figures originally embodied so memorably by Glen Hansard and Marketa Irglova, who also wrote the music and lyrics. Here, they are played by Steve Kazee, so Adonis-hunky that it’s a wonder that his character hasn’t already reached stardom of Bruce Springsteen proportions, and Cristin Milioti, so cutely adorable that she should be the star of her own sitcom.

Since the stage production couldn’t exactly replicate the streets of Dublin, Bob Crowley’s evocative set recreates the most Irish thing imaginable—a pub. Indeed, before the show starts, the cast members are up on stage having a rowdy time singing and playing musical instruments, with audience members welcome to come up and buy drinks at the “bar,” free to either linger for a while onstage or bring them back to their seats.

The ensemble--many of them doubling as musicians--sits around the perimeter of the set when not involved in the action. Among the standouts are David Patrick Kelly, as the Guy’s elderly Da; Paul Whitty, as a protective friend of the Girl; and Andy Taylor, as a bank manager comically self-deluded about his own musical talents.

The score, all of which comes from the film, retains its folksy appeal, even if it’s not particularly theatrical--the standout, not surprisingly, is the gorgeous, Oscar-winning “Falling Slowly.” It’s all beautifully sung by the cast who—thanks to the movement choreographed by Steven Hoggett (Black Watch)—also imbue their musicianship with tremendous physicality.

The book by Irish playwright Enda Walsh (Penelope, The Walworth Farce) is rather too elongated, but it’s also undeniably witty and certainly sharper than the film version, which had a semi-improvised feel. And John Tiffany has staged the proceedings with a smooth fluidity that keeps the action flowing nicely.

I wish I could say that I fell in love with Once the way that I suspect many audiences are bound to. But then again, that’s the way love is, isn’t it?

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